Prognostic significance of p27 and ki-67 expression in mucoepidermoid carcinoma of the intraoral minor salivary gland

Prognostic Significance of p27 and Ki-67 Expression in Mucoepidermoid Carcinoma of the Intraoral Minor Salivary Gland
Mitsukuni Okabe, D.M.D., Hiroshi Inagaki, M.D., Takayuki Murase, M.D., Masahisa Inoue, D.M.D., Noriyuki Nagai, D.M.D., Tadaaki Eimoto, M.D. Department of Pathology (MO, HI, TM, TE), Nagoya City University Medical School, Nagoya, Japan; and Department of Oral Pathology (MI, NN), Okayama University Dental School, Okayama, Japan

p27 and Ki-67, a universal cyclin-dependent kinase inhibitor and a proliferative cell marker, respectively, have been useful in predicting clinical aggressiveness in various human tumors. We studied clinicopathologic significance of these molecules in mucoepidermoid carcinoma of the intraoral minor salivary gland. Expression of p27 and Ki-67 was assessed immunohistochemically in primary mucoepidermoid carcinomas from 31 patients without distant metastasis at surgery. Correlation each of p27 and Ki-67 expression was analyzed with various clinicopathologic parameters including age, sex, primary tumor site, tumor size, nodal metastasis, clinical stage, and histologic grade. The latter was evaluated using a point-scoring scheme of Auclair et al. that consists of five histologic factors (intracystic component, neural invasion, necrosis, mitosis, and anaplasia). p27 expression was correlated inversely with histologic grade (P .007), but with none of other factors. When the correlation of p27 expression was further examined with each of the histologic factors, it was correlated significantly with intracystic component, but not with neural invasion, necrosis, mitosis, or anaplasia. Ki-67 expression was correlated significantly with histologic grade only in the clinicopathologic factors (P < .0001), and in the histologic factors, with necrosis, mitosis, and anaplasia. Multivariate prognostic analyses were performed to identify independent risk factors for both disease-free and overall survivals. Large tumor size (P .031, relative